Disk drive with a thermal asperity reduction circuitry using a magnetoresis sensor

Claim 2

A magnetoresistive (MR) sensor, comprising: an MR element, said MR element including an MR layer, a spacer, and a soft adjacent layer (SAL), said MR layer separated from said SAL by said spacer; first and second hard bias layers separated from each other by said MR element, said first and second hard bias layers forming contiguous junction with said MR element; an electrical insulator; an asperity compensation layer (ACL) separated from said MR element and said hard bias layers by said electrical insulator; first and second MR leads disposed over said first and second hard bias layers for providing sense current to said MR element; and first and second ACL leads disposed over said ACL for providing current to said ACL.

Claim 3

An MR sensor as recited in claim 1 wherein said ACL comprises NiFe.

Claim 4

An MR sensor according to claim 2, further including an antiferromagnetic (AFM) layer for pinning the magnetization of said ACL, said ACL being disposed over said AFM layer.

Claim 5

An MR sensor as recited in claim 1 wherein said MR layer is selected from a group of material consisting of NiFe and NiFe/Co.

Claim 6

An MR sensor as recited in claim 1 wherein said ACL is selected from a group of material consisting of copper and tantalum.

Claim 7

An MR sensor as recited in claim 3 wherein said AFM layer is selected from a group of material comprising FeMn, NiMn and NiO.

Claim 8

An MR sensor as recited in claim 1 wherein said first and second hard bias layers are selected from a group of material comprising CoPtCr, CoPtCrTa, and CoPtCrSiO 2 .

Claim 9

A magnetic storage system, comprising: a magnetic storage medium for recording data; a magnetoresistive (MR) sensor for reading information from said magnetic storage medium, said MR sensor comprising: an MR element, said MR element including an MR layer, an spacer, and a soft adjacent layer (SAL), said MR layer separated from said SAL by said spacer; first and second hard bias layers separated from each other by said MR element, said first and second hard bias layers forming contiguous junction with said MR element; an electrical insulator; an asperity compensation layer (ACL) separated from said MR element and said hard bias layers by said electrical insulator; first and second MR leads disposed over said first and second hard bias layers for providing sense current to said MR element; and first and second ACL leads disposed over said ACL for providing current to said ACL; and a recording channel coupled to said MR sensor for detecting resistance changes in said MR sensing element responsive to applied magnetic fields representative of data recorded in said magnetic storage medium.

Claim 10

A magnetic storage system, comprising: a magnetic storage medium for recording data; a magnetoresistive (MR) sensor for reading information from said magnetic storage medium, said MR sensor comprising: an MR element, said MR element including an MR layer, an spacer, and a soft adjacent layer (SAL), said MR layer separated from said SAL by said spacer; first and second hard bias layers separated from each other by said MR element, said first and second hard bias layers forming contiguous junction with said MR element; an electrical insulator; an asperity compensation layer (ACL) separated from said MR element and said hard bias layers by said electrical insulator; first and second MR leads disposed over said first and second hard bias layers for providing sense current to said MR element; and first and second ACL leads disposed over said ACL for providing current to said ACL; and a recording channel coupled to said MR sensor for detecting resistance changes in said MR sensing element responsive to applied magnetic fields representative of data recorded in said magnetic storage medium.

Claim 11

An MR sensor as recited in claim 8 wherein said ACL comprises NiFe.

Claim 12

A magnetic storage system according to claim 9, further including an antiferromagnetic (AFM) layer for pinning the magnetization of said ACL, said ACL being disposed over said AFM layer.

Claim 13

A magnetic storage system according to claim 8, wherein said MR layer is selected from a group of material consisting of NiFe and NiFe/Co.

Claim 14

A magnetic storage system according to claim 8, wherein said ACL is selected from a group of material consisting of copper and tantalum.

Claim 15

A magnetic storage system according to claim 8, wherein said AFM layer is selected from a group of material comprising FeMn, NiMn and NiO.

Claim 16

A magnetic storage system according to claim 8, wherein said first and second hard bias layers are selected from a group of material comprising CoPtCr, CoPtCrTa, and CoPtCrSiO 2 .

Claim 17

A magnetic storage system according to claim 8, wherein said recording channel further comprises a differential circuit having a first and second input terminals connected to the first MR lead and the first ACL lead, respectively, for detecting resistance changes in said MR sensing element and said ACL responsive to a thermal asperity phenomena during reading data in said magnetic storage medium.